"""

========================================

Projecting contour profiles onto a graph

========================================

Demonstrates displaying a 3D surface while also projecting contour 'profiles'

onto the 'walls' of the graph.

See contourf3d_demo2 for the filled version.

"""

from mpl_toolkits.mplot3d import axes3d

import matplotlib.pyplot as plt

from matplotlib import cm

ax = plt.figure().add_subplot(projection='3d')

X, Y, Z = axes3d.get_test_data(0.05)

# Plot the 3D surface

ax.plot_surface(X, Y, Z, rstride=8, cstride=8, alpha=0.3)

# Plot projections of the contours for each dimension. By choosing offsets

# that match the appropriate axes limits, the projected contours will sit on

# the 'walls' of the graph

cset = ax.contour(X, Y, Z, zdir='z', offset=-100, cmap=cm.coolwarm)

cset = ax.contour(X, Y, Z, zdir='x', offset=-40, cmap=cm.coolwarm)

cset = ax.contour(X, Y, Z, zdir='y', offset=40, cmap=cm.coolwarm)

ax.set_xlim(-40, 40)

ax.set_ylim(-40, 40)

ax.set_zlim(-100, 100)

ax.set_xlabel('X')

ax.set_ylabel('Y')

ax.set_zlabel('Z')

plt.show()